Chlorinated unsaturated hydrocarbonisothiocyanate synergistic nematocidal compositions and method



United States Patent CHLORINATED UNSATURATED HYDROCARBON- TSOTHEOCYANATESYNERGHSTTC NEMATOCI- DAL (IOMPOSITHONS AND METHOD Constantine Katsaros,Crystal Lake, llll., and Clare B. Kenaga, Lake Geneva, Wis, assignors toMorton Salt (Zompany, Chicago, Ill., a corporation of Delaware NoDrawing. Filed Aug. 23, 1962, Ser. No. 218,837

7 Claims. (Cl. 167-22) This invention relates to nematocidalcompositions and more particularly to synergistic nematocidalcompositions containing 1,4-dichloro-2-butene, 1,3-dichloro-2-butene or1,4-dichloro-2-butyne.

Certain isothiocyanates have been used in the control of nematodes withvariable results. One such material is allyl isothiocyanate (also knownas mustard oil) which has been shown to be an effective nematocide incontact tests or when applied to nematode infestations. HoW- ever, ithas been found that allyl isothiocyanate loses its practicaleffectiveness as a nematocide particularly when applied to nematodeinfestations in an organic, loam, or muck soil to such an extent as tobe considered substantially inactive.

It has been found, however, that the drawbacks inherent in tie use ofallyl and other organic isothiocyanates can be largely eliminated orminimized by the incorporation therewith of an unsaturated chlorinatedhydrocarbon from the group of 1,4-dichloro-2-butene,1,3-dichloro-2-butene and 1,4-dichloro-2-butyne. It has also been foundthat the combination of isothiocyanate and dichlorobutene ordichlorobutyne results in a synergism, the resultant compositions havingunexpectedly high activity as a nematocide and greater effectivenessthan either compound when used alone.

Accordingly, in one broad form, the present invention comprises theprovision of a synergistic nematocidal composition comprising anadmixture of a compound selected from the group consisting of1,4-dichloro-2-butene, 1,3- dichloro-Z-butene and 1,4-dichloro-2-butynewith a compound selected from the group consisting of alkyl, alkenyl,and cycloalkyl isothiocyanates.

A further aspect of the present invention is the provision of a processfor controlling nematodes in soils which comprises applying to nematodesand their habitats a composition containing an admixture of1,3-dichloro-2- butene, 1,4-dichloro-2-butene or 1,4-dichloro-2-butyneand an isothiocyanate selected from the group consisting of alkylisothiocyanates, alkenyl isothiocyanates and cycloalkyl isothiocyanates.

The alkyl and the alkenyl isothiocyanates contemplated for use in thesynergistic compositions of this invention are lower alkyl and alkenylisothiocyanates'preferably wherein said alkyl or alkenyl substituentscontain up to about '6 carbon atoms. Exemplary of such substituents aregroups, such as methyl, ethyl, N-propyl, isopropyl, butyl, amyl,isoamyl, allyl, butenyl and the like. With respect to cycloalkylderivatives, substituents containing up to 8 carbon atoms arecontemplated, exemplified by cyclohexyl, cyclopentyl, methylcyclopentyl,methylcyclohexyl and dimethylcyclohexyl isothiocyanate.

The organic isothiocyanate and chlorinated unsaturated hydrocarbon maybe present in varying proportions, preferably however, the organicisothiocyanate is present in amounts of from to 50 percent (by weight)and the chlorinated hydrocarbon in amounts of from 50 to 95 ercent. Inthe most preferred form the isothiocyanate constitutes from 10 to 30percent and the chlorinated unsaturated hydrocarbon from 70 to 90percent, said percentages being based on the relative proportions of thenamed components Alternatively, the perecntages may "ice be expressed asratios of parts by weight of the components, i.e., containing from 5 to50 parts isothiocyanate and from 50 to parts by weight of chlorinatedhydrocarbon, and preferably containing from 10 to 30 partsisothiocyanate and from 70 to '90 parts chlorinated hydrocarbon.

Since the nematocidal compositions of this invention may be utilized invarious forms including formulations containing diluents or carriers,the recited percentages have reference to the isothiocyanate andchlorinated unsaturated hydrocarbon components without reference to anyancillary diluents.

The following procedure Was utilized in evaluating the toxicity andeffectiveness as a nematocide of the compositions of the presentinvention.

TEST PROCEDURE The product to be tested is dissolved inN,N-dimethylformamide in at least a 5% concentration. One end of a5-inch glass tube, having a 1 inch I.D., is corked and the tube filledwith about 57 grams of black loam soil, previously adjusted to a 20%moisture level and passed through a No. 12 sieve (US. Standard SieveSeries). The soil is gently and evenly compacted in the tube. Whencompacted, the soil column is 3% to 3 /2 inches long. A onefourth inchlayer of dry sea sand is then added. Nematodes to be tested are removedfrom an oatmeal culture by means of the Baerman funnel technique usingphysiological saline, 0.85% sodium chloride. The concentration ofnematodes should be between 12,000 to 15,000 nematodes per cc. with avolume of 35-50 ml. By means of a medicine dropper 4-6 drops of thenematode suspension (30005()O() nematodes) are distributed evenly overthe surface of the sand. An additional /4 inch layer of dry sea sand isadded to the tube and moistened with 1 ml. of physiological saline. Athin polyethylene film is placed over the open end of the tube and acork pushed into the tube to the point of contact with the sand. Thetube is then inverted and the first cork removed. A small depression ismade in the soil with a glass rod. The solution to be tested is pipettedinto the tube in the depression. The compound to be tested is added inthe desired amount. After addition of the test compound the open end ofthe tube is covered with a thin film of polyethylene and recorked. Alltreatments are replicated three times. The tubes are left in the dark at80 F. in an upright position (nematodes at the bottom of the tube) for48 hours.

To determine the effectiveness of the compound, the sea sand containingthe nematodes is removed from the tube and flushed with 10 ml. ofphysiological saline, and the saline solution decanted to a watch glass.The count on the check is carried out by noting the number of nematodesin the check required to give live nematodes. The figure obtained isused as a basis of count in the counting of the treated nematodes. Thefollowing results were obtained using Panagrellus redivivus as the testnematode.

The following tables illustrate the synergistic nematocidal effectobtained by the use of an admixture of an organic isothiocyanate with1,4-dichloro-2-butene, 1,3-dichloro-Z-butene, or 1,4-dichloro-2-butyne.The test procedure was as described above. The dosage is given inmicrograms g) per tube in each test. The degree of synergism is shown interms of increase in percent kill over the theoretical.

Table A shows the results obtained by the use of methyl isothiocyanatealone, 1,4-dichloro-2-butene alone and by the use of a mixture of thecompounds.

Table B shows the results obtained by the use of methyl isothiocyanatealone, 1,3-dichloro-2-butene alone, and by the use of a mixture of thecompounds.

3 Table C shows the results obtained by the use of 1,41dichloro-Z-butyne alone, methyl isothiocyanate alone and by the use of amixture of the compounds.

Table A Nematocidal Composition, Conccn- Theoretitration in gJtube calPercent Amount Actual Kill 01 Syner- Kill Based on gism 1,4di- Methyl-Additive chloroisothio- Efiects Z-butene cyanatc Table B N ematocidalComposition, Oonccn- Theoreti tration in gJtube cal Percent AmountActual Kill of Syn- Kill Based on crgism 1,3-di- Methyl- Additivechloroisothio- Eflects 2-butene cyanate Table C Nematocidal Composition,Concen- Theoretitration in g/tube cal Percent Amount Actual Kill of Syn-Kill Based on ergism 1,4- di- Methyl- Additive chloroisothio- Effects2-butyne cyanate While the foregoing compositions may readily be appliedto loam soils in their undiluted form, it is also true that they may, ifdesired, be applied in conjunction with diluents or carriers which areinert or inactive to aid in the distribution of the active synergisticcomposition. For example, solvents, such as deodorized kerosene,ketones, esters, alcohols, chlorinated hydrocarbons and variouslow-boiling petroleum fractions, may be utilized in conjunction with thepresent synergistic compositions. In addition to organic solventcarriers of the type described above, the present nematocidalcompositions may be applied in the form of emulsions, dispersions or thelike. The amount of material varies of course with the type ofinfestation and the characterof the particular area to be treated, butapplication of the compositions at rates from about 2 to about 100gallons per acre is satisfactory.

It is also contemplated that admixtures of one or more of theunsaturated chlorinated hydrocarbons may be employed with one or severalof the organic isothiocyanates described in the foregoing.

While several embodiments of this invention are shown above, it will beunderstood that the invention is not limited thereto, since manymodifications may be made, and it is contemplated, therefore, by theappended claims, to cover any such modifications as fall within the truespirit and scope of this invention.

We claim:

1. A synergistic nematocidal composition comprising an admixturecontaining on a relative proportion basis from about 50 to percent byweight of a chlorinated unsaturated hydrocarbon selected from the groupconsisting of 1,4-dichloro-2-butene, 1,3-dichloro-2-butene and1,4-dichloro-2-butyne and from about 5 to about 50 percent by weight ofmethyl isothiocyanate.

2. The composition of claim 1 wherein the chlorinated unsaturatedhydrocarbon is 1,4-dichloro-2-butene.

3. The composition of claim 1 wherein the chlorinated unsaturatedhydrocarbon is 1,3-dichloro-2-butene.

4. The composition of claim 1 wherein the chlorinated unsaturatedhydrocarbon is 1,4-dichloro-2-butyne.

5. A synergistic nematocidal composition comprising an admixturecontaining on a relative proportion basis from about 50 to 95 percent byweight of a chlorinated unsaturated hydrocarbon selected from the groupconsisting of 1,4-dichloro-2-butene, 1,3-dlchloro-2-butene and1,4-dichloro-2-butyne and from about 5 to about 50 percent by weight ofmethyl isothiocyanate and a carrier therefor.

6. A process for controlling nematode infestations in soils whichcomprises applying to nematodes and their habitats an admixturecontaining on a relative proportion basis from about 50 to 95 percent byweight of a chlorinated unsaturated hydrocarbon selected from the groupconsisting of 1,4-dichloro-2-butene, 1,3-dichloro-2-butene and1,4-dichloro-2-butyne and from about 5 to 50 percent by weight of methylisothiocyanate.

7. The process of claim 6 wherein the admixture is applied inconjunction with a carrier.

References Cited in the file of this patent UNITED STATES PATENTS2,057,044 Meisenburg et al Oct. 13, 1936 2,112,688 Bousquet Mar. 29,1938 2,824,887 Klopping Feb. 25, 1958 2,849,366 Youngson et al. Aug. 26,1958

1. A SYNERGISTIC NEMATOCIDAL COMPOSITION COMPRISING AN ADMIXTURECONTAINING ON A RELATIVE PROPORTION BASIS FROM ABOUT 50 TO 95 PERCENT BYWEIGHT OF A CHLORIDATED UNSATURATED HYDROCARBON SELECTED FROM THE GROUPCONSSISTING OF 1,4-DICHLORO-2-BUTENE, 1,3-DICHLORO-2-BUTENE AND1,4-DICHLORO-2-BUTYNE AND FROM ABOUT 5 TO ABOUT 50 PERCENT BY WEIGHT OFMETHYL ISOTHIOCYANATE.